Video system for use with video telephone and video conferencing

ABSTRACT

This invention provides a video system including an image pickup device for converting an optical image into a video signal, an image pickup direction changing device for changing the image pickup direction of the image pickup device, an image display device for displaying the video signal output from the image pickup device, and a function display device for displaying function information of the image pickup device.

This application is a continuation of application Ser. No. 08/801,367filed Feb. 19, 1997, now U.S. Pat. No. 6,665,006 which is a continuationof application Ser. No. 08/307,141 filed Sep. 16, 1994, now abandonedthe entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a video system for video telephones andvideo conferences using video cameras and the like.

2. Description of the Related Art

In recent years, along with the development of microprocessors which canrealize high-speed arithmetic operations, personal computers,workstations, and the like for multimedia information can process alarge volume of image information and audio information in real time.More specifically, personal computers and workstations can realize adevice for reading out a full-color moving image signal, an audiosignal, and the like from a CD-ROM, and reproducing these signals inassociation with each other, and a video conference or video telephonefunction of achieving a conference such as a meeting by converting amoving image signal and an audio signal from a video camera into digitalsignals, and transmitting compressed digital signals to a remote stationvia a communication line.

In the video telephone or video conference function utilizing a personalcomputer or workstation, a video camera is arranged on or near amonitor. Recently, a system which can control the video camera inaccordance with commands from the personal computer or workstation by asimple operation has been developed.

However, when the video telephone or video conference function isrealized using a combination of a personal computer or workstation witha video camera, different device driver software programs must beprepared and selectively used in correspondence with the sensor sizesand functions of video cameras, resulting in inconvenience for anoperator. In order to detect a photographing range in direction or zoomcontrol of the camera, the range must be confirmed by operating thecamera to the limit of the direction or zoom control, and a cumbersomeoperation is required for displaying a required image on a monitor,resulting in poor operability. Furthermore, in the video conference orvideo telephone function, since the direction and zooming of the cameracan be controlled by the remote station side, an image includingcontents which are not to be disclosed to a third party is undesirablytransmitted to the remote station, thus posing a problem associated withprotection of privacy.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a video system whichcan solve the above-mentioned problems, and is easy to use.

It is another object of the present invention to provide a video systemwith high operability.

It is still another object of the present invention to provide a videosystem which can obtain a required image.

In order to achieve the above objects, according to one aspect of thepresent invention, an optical image is converted into a video signal byan image pickup means, the image pickup direction of the image pickupmeans is changed by an image pickup direction changing means, the videosignal output from the image pickup means is displayed on an imagedisplay means, and function information of the image pickup means isdisplayed on a function information display means. With thisarrangement, the image pickup direction of the image pickup means can befreely changed by the receiving station side, and a video system whichis very easy to use can be provided. Since the function information ofthe image pickup means is displayed, an operator can recognize functionsat a glance, and need not operate the image pickup means to confirm thefunctions.

According to another aspect of the present invention, an optical imageis converted into a video signal by an image pickup means, the imagepickup direction of the image pickup means is changed by an image pickupdirection changing means, the video signal output from the image pickupmeans is stored as a still image in a still image storage means, theimage pickup direction of the image pickup means upon photographing ofthe still image is stored in a photographing direction storage means,the still image stored in the still image storage means is displayed ona still image display means, a moving image output from the image pickupmeans is displayed on a moving image display means, the position on thestill image displayed on the still image display means is designated bya designation means, and the photographing direction change means iscontrolled, so that the position designated by the designation meansbecomes a predetermined position of an image. With this arrangement, theimage pickup direction of the image pickup means can be freely changedby the receiving station side, and control is made, so that thedesignated position on the stored still image becomes a predeterminedposition of an image. For this reason, a video system which isconvenient and allows for simple operation can be provided.

According to still another aspect of the present invention, an opticalimage is converted into a video signal by an image pickup means, theimage pickup direction of the image pickup means is changed by an imagepickup direction changing means, a video signal within a photographablerange of the image pickup direction changing means is stored, and thestored video signal is displayed. With this arrangement, the imagepickup direction can be freely changed by the receiving station side,and an image within the stored photographable range is displayed. Forthis reason, since an operator can know the photographable range at aglance, a very efficient video system can be provided.

Other objects and features of the present invention will become apparentfrom the following specification and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the arrangement of the entire controlapparatus for an image input device according to the first embodiment ofthe present invention;

FIG. 2 is a block diagram showing the arrangement of an imagesynthesization circuit;

FIG. 3 is a schematic diagram showing the arrangement of a video camera;

FIG. 4 is a diagram showing a state wherein video cameras are connectedto the control apparatus;

FIG. 5 is a view showing a state wherein images of objects are picked upby the video camera and are displayed on a monitor;

FIGS. 6A and 6B are views showing the positional relationship betweenmoving images on a display picture and objects;

FIG. 7 is a view showing the relationship between the focal length of alens and the photographable angle of view of a CCD;

FIG. 8 is a table showing control commands for controlling variousoperations;

FIG. 9 is a table showing the status format of the video camera;

FIG. 10 is a table showing the function information format of the videocamera;

FIG. 11 is a flow chart showing the control sequence of the firstembodiment;

FIG. 12 is a flow chart showing the control sequence of the firstembodiment;

FIG. 13 is a flow chart showing the control sequence of the firstembodiment;

FIG. 14 is a block diagram showing the arrangement of an imagesynthesization circuit as the second embodiment of a control apparatusfor a video camera according to the present invention;

FIG. 15 is a table showing an example of data stored in a still imagestoring unit of the image synthesization circuit;

FIG. 16 is a view showing a state wherein both a still image and amoving image are displayed on a display picture;

FIGS. 17A and 17B are views showing the positional relationship betweena display on a moving image region and objects at that time;

FIGS. 18A and 18B are views showing a display on the moving image regionand the direction of the video camera at that time;

FIGS. 19A and 19B are views showing a display on the moving image regionand the direction of the video camera upon completion of directioncontrol of the video camera;

FIG. 20 is a flow chart showing the control sequence of the secondembodiment;

FIG. 21 is a flow chart showing the control sequence of the secondembodiment;

FIG. 22 is a flow chart showing the control sequence of the secondembodiment;

FIG. 23 is a flow chart showing the control sequence of the secondembodiment;

FIG. 24 is a block diagram showing the arrangement of a controlapparatus for a video camera according to the third embodiment of thepresent invention;

FIG. 25 is a view showing a state wherein both a still image and amoving image are displayed on a display picture in the third embodiment;

FIG. 26 is a block diagram showing the arrangement according to thefourth embodiment of the present invention;

FIG. 27 is a view illustrating a video conference;

FIG. 28 is a view showing a monitor screen during the video conference;

FIG. 29 is a perspective view showing pan and tilt drive systems;

FIG. 30 is a plan view for explaining pan movement;

FIG. 31 is a plan view for explaining pan movement;

FIG. 32 is a plan view for explaining pan movement;

FIG. 33 is a plan view for explaining pan movement;

FIG. 34 is a side view for explaining tilt movement;

FIG. 35 is a view showing an example of the entire display of all imageswithin a photographing range;

FIG. 36 is a block diagram showing the circuit arrangement of an imagestoring unit;

FIG. 37 is a flow chart showing the operation of the fourth embodiment;

FIG. 38 is a flow chart showing the operation of the fourth embodiment;

FIG. 39 is a flow chart showing the operation of the fourth embodiment;

FIG. 40 is a flow chart showing the operation of the fourth embodiment;

FIG. 41 is a flow chart showing the operation of the fourth embodiment;

FIG. 42 is a flow chart showing the operation of the fourth embodiment;

FIG. 43 is a view showing an example of setting of a photographingprohibition image;

FIG. 44 is a view showing the relationship between the focal length of alens and the angle of view;

FIG. 45 is a block diagram showing the arrangement according to thefifth embodiment of the present invention;

FIG. 46 is a circuit diagram of a video image superimposing circuithaving a function of an image storing device;

FIG. 47 is a view showing an example of the entire display ofphotographing range images without boundaries; and

FIG. 48 is a table showing the transmission format of camera controlcommands.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments of the present invention will be described indetail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the first embodiment of a controlapparatus for a video camera which is applied to a video systemaccording to the present invention. The control apparatus 1 has thefollowing arrangement. That is, a storage unit 2 which comprises a ROMfor storing a control program and the like and a RAM for temporarilystoring various data during a control operation, a DMA (Direct MemoryAccess) controller 3, an FD controller 5 for controlling a flexible disk4, and an HD controller 7 for controlling a hard disk 6 are connected toa CPU (central processing unit) 9 via an address/data bus 8 (to bereferred to as a “bus” hereinafter). The CPU 9 is connected to a videosignal display image synthesization circuit 10 (to be referred to as an“image synthesization circuit” hereinafter) via the bus 8, and the imagesynthesization circuit 10 is connected to a monitor 11 and a pluralityof video cameras 13. More specifically, the image synthesization circuit10 performs predetermined display processing on the basis of a videosignal from each video camera 13, and outputs the video signal to themonitor 11. Furthermore, the CPU 9 is connected to an interfacecontroller 12 via the bus 8, and the interface controller 12 isconnected to the plurality of video cameras 13. These video cameras 13and the interface controller 12 can perform bidirectionaltransmission/reception of control commands therebetween. Morespecifically, the interface controller 12 generates a transmissionrequest signal for requesting transmission of, e.g., functioninformation of each video camera 13. On the other hand, the videocameras 13 transmit control commands such as function information to theinterface controller 12 in response to the transmission request signal,and supply predetermined video signals to the image synthesizationcircuit 10. The CPU 9 is connected to a position storing unit 14 and amouse controller 16 via the bus 8. The position storing unit 14 storesposition information of each video camera 13 corresponding to an imagedisplayed on the monitor 11. The mouse controller 16 is connected to apointing device such as a mouse 15, and controls its operation.

The image synthesization circuit 10 has an arrangement, as shown indetail in FIG. 2. A superimposing controller 17 is connected to the bus8 via a data signal line L0, a control signal line L1, and a positioninformation line L2 to execute an image synthesization operation. Thedata signal line L0 is connected to a buffer 18, and the positioninformation line L2 is connected to a pointing position recognizingcircuit 19 for recognizing the pointing position on a picture or screen.

The data signal line L0 and the control signal line L1 are connected toa mouse cursor generation circuit 20 for generating a mouse cursor, anda bus interface 21 for performing an interface operation with the bus 8.Furthermore, the mouse cursor generation circuit 20 and the businterface 21 are connected to a VGA (Video Graphics Array) displaysignal generating circuit 22 for outputting a VGA display signal, andthe VGA display signal generating circuit 22 is connected to a displaytiming generation circuit 23 for setting a display timing, a DRAM(dynamic random access memory) 24, the pointing position recognizingcircuit 19, and the superimposing controller 17.

On the other hand, an A/D converter 25 which receives a video signalfrom each video camera 13 is connected to a digital video decoder 26 fordecoding the video signal. The digital video decoder 26 is connected toa mirror image conversion circuit 27 for performing mirror imageconversion. The mirror image conversion circuit 27 horizontally reversesa video signal, and displays an image on the monitor 11 as if the imagewere reflected in a mirror. More specifically, the mirror imageconversion circuit 27 writes an input video signal for one line in,e.g., a line memory in the input order, and reads out the informationwritten one line before in the reverse direction at the timing of thenext line. Then, a current input signal is written at the readoutaddress, thus achieving full-line mirror image reversal.

The mirror image conversion circuit 27 is connected to the superimposingcontroller 17. The superimposing controller 17 is connected to a TTL(Transistor Transistor Logic) switch circuit 28, which performs logicprocessing of a signal, directly or via a VRAM (video random accessmemory) 29. Furthermore, the TTL switch circuit 28 is connected to a D/Aconverter 30.

The A/D converter 25, the digital video decoder 26, the mirror imageconversion circuit 27, and the superimposing controller 17 are connectedto a PLL (Phase-locked loop) circuit 31, and the VGA display signalgenerating circuit 22 is connected to the TTL switch circuit 28 via acolor palette 32.

In the image synthesization circuit 10, an analog video signal inputfrom each video camera 13 is converted into a digital signal via the A/Dconverter 25, and the digital signal is decoded by the digital videodecoder 26, thus generating RGB (Red, Green, and Blue) signals. The RGBvideo signals are input to the mirror image conversion circuit 27 andare subjected to mirror image conversion. Thereafter, the RGB signalsare input to the superimposing controller 17. Then, the RGB videosignals are temporarily stored in the VRAM 29, and are read out insynchronism with the VGA display signal generating circuit 22. Thereadout RGB signals are synthesized with a VGA signal by the TTL switchcircuit 28, and the synthesized composite signals are converted by theD/A converter 30 into an analog signal. The converted analog signal isoutput to the monitor 11 as a video signal. More specifically, the VRAM29 constantly stores input video signals, and the video signals are readout asynchronously with the storage operation but synchronously with theVGA display signal generating circuit 22.

FIG. 3 is a schematic diagram showing a drive device and circuit foreach video camera 13. Each video camera 13 comprises a stationaryportion 33 and a movable portion 34. The movable portion 34 is attachedto the stationary portion 33 to be movable in the pan and tiltdirections.

More specifically, the stationary portion 33 incorporates a drive devicefor rotating the video camera 13 in the pan and tilt directions, acontrol circuit for controlling the drive device, and a video circuitfor outputting a video signal.

The drive device comprises, as major components, a pan cogwheel 39 forrotating the movable portion 34 in the pan direction (indicated by anarrow A in FIG. 3) via a pan shaft 38, a pan control motor 40 fortransmitting the drive force to the pan cogwheel 39, a tilt cogwheel 41for rotating the movable portion 34 in the tilt direction (indicated byan arrow B in FIG. 3) via a tilt shaft (not shown), and a tilt controlmotor 42 for transmitting the drive force to the tilt cogwheel 41.

The control circuit comprises an external interface circuit 43 forperforming an interface operation with the control apparatus, anoperation processing unit 44, and an input/output (I/O) port 45 forsupplying control signals to the pan control motor 40 and the tiltcontrol motor 42 in accordance with the operation result of theoperation processing unit 44.

Furthermore, the video circuit comprises a process circuit 46 for, e.g.,separating an output signal from the movable portion 34 into a luminancesignal Y and a chrominance signal C, and a video encoder circuit 47 foroutputting a predetermined video signal.

On the other hand, the movable portion 34 comprises a lens 48, a zoomlens 49, a zoom control circuit 50 for controlling the zoom lens 49, aniris 51, an iris control circuit 52 for controlling the iris 51, a CCD53 for converting an optical image of an object into an electricalsignal, and a CCD read-out circuit 54 for reading out an electricalsignal converted by the CCD 53 and transmitting the readout signal tothe process circuit 46.

In the video camera, the zoom position is set by the zoom controlcircuit 50 and the iris is set by the iris control circuit 52. Anoptical image of an object is formed on the CCD 53 via the lens 48 andthe zoom lens 49, and is photoelectrically converted into a videosignal. The video signal is output from a video terminal t1 via theprocess circuit 46 and the video encoder circuit 47. Also, a controlsignal is input from a control terminal t2 to the pan control motor 40and the tilt control motor 42 via the external interface circuit 43, theoperation processing unit 44, and the I/O port 45 so as to attainrotation control in the pan and tilt directions.

FIG. 4 shows a state wherein various video cameras 13 a to 13 e to becontrolled are connected to the control apparatus 1. In FIG. 4, variousvideo cameras 13 a to 13 e having different sensor sizes and operationfunctions are connected to the control apparatus 1 via a switch 55. Morespecifically, the switch 55 has terminals 56 a to 56 e, and one of theterminals 56 a to 56 e is selected by a switching control signal 57 fromthe control apparatus 1. One of the video cameras 13 a to 13 e connectedto the selected terminal exchanges signals with the control apparatus 1via a signal line 57′.

More specifically, the terminal 56 a is connected to a video camera 13 awhich comprises a 1″ CCD sensor as an image pickup unit 58 a, and haspan and tilt functions, and the terminal 56 b is connected to a videocamera 13 b which comprises a ⅔″ CCD sensor as an image pickup unit 58 band has pan and tilt functions. The terminal 56 c is connected to avideo camera 13 c which comprises a ½″ CCD sensor as an image pickupunit 58 c and has only a pan function, and the terminal 56 d isconnected to a head-separated fixed camera 13 d which comprises a ⅓″ CCDsensor as an image pickup unit 58 d. Furthermore, the terminal 56 e isconnected to a hi-vision video camera 13 e which comprises a 1″ CCDsensor as an image pickup unit 58 e. Note that the present invention isnot limited to the above-mentioned video cameras 13 connected to theterminals 56 a to 56 e, and video cameras 13 having arbitrary sensorsizes can be connected to these terminals.

FIG. 5 shows a state wherein object persons A, B, and C are photographedby the video camera 13 a, and their images are displayed on a displaypicture 59. An iris control cursor 60, a pan control cursor 61, a zoomcontrol cursor 62, and a tilt control cursor 63 are respectivelyarranged at the upper, lower, left, and right positions on the displaypicture 59. By designating the iris control cursor 60, the iris controlcircuit 52 is driven to control the brightness on the display picture59. When an auto iris mode is set, iris data included in statusinformation from the video camera 13 is received to control the iriscontrol cursor 60. On the other hand, by designating the zoom controlcursor 62, the zoom lens 49 is moved via the zoom control circuit 50. Anoperator M operates the mouse 15 while observing the monitor 11 toperform display control of object persons on the display picture 59.Note that a mouse cursor 15 a is generated by the mouse cursorgeneration circuit 20 upon operation of the mouse 15.

In FIG. 5, the video camera 13 a is operated to display the objectperson B at the central position of the display picture 59 at thepresent time. For example, the video camera 13 a can beremote-controlled to display the object person A at the central positionof the display picture.

The control method will be described below with reference to FIGS. 6A to7.

FIG. 6A shows object persons displayed on the display picture 59 of themonitor 11. In FIG. 6A, the distance between the object persons A and Bon the display picture 59 is Λ, and the horizontal distance of thedisplay picture 59 is L. FIG. 6B is a plan view of a photographing room.In FIG. 6B, the moving angle of the video camera 13 a required fordisplaying the object person A at the central position of the displaypicture 59 is θ. FIG. 7 shows the relationship between a focal length fof the lens 48 and a photographable angle W of view of the CCD 53.Referring to FIG. 7, if the horizontal effective distance of the CCD 53is represented by X, a distance φ between the object persons A and B onthe CCD 53, the moving angle θ of the video camera 13 a, and the angle Wof view are respectively given by the following equations (1) to (3):φ=X·1/L  (1)θ=tan⁻¹φ  (2)W=2 tan⁻¹(X/2f)  (3)

As can be understood from equation (1), the horizontal effectivedistance X of the CCD 53 is required for calculating the moving angle θin the pan direction, and similarly, a vertical effective distance Y(not shown) of the CCD 53 is required for calculating the moving anglein the tilt direction.

Therefore, when an operator operates to sequentially switch theplurality of video cameras 13 a to 13 e having CCDs 53 of differentsizes and to direct one of the video cameras 13 in the target objectdirection, by grasping the horizontal effective distances X and thevertical effective distances Y of the CCDs 53 used in the video cameras13 a to 13 e, the control apparatus 1 can generate drive commands to thepan control motor 40 and the tilt control motor 42 to set a moving angleθ suited for one of the video cameras 13 a to 13 e as an apparatus to becontrolled. Therefore, the operator M can easily perform operationregardless of the types of the video cameras 13 a to 13 e.

The distance Λ on the display picture 59 and the horizontal distance Lof the display picture 59 are read out from the superimposing controller17 and the pointing position recognizing circuit 19 via the bus 8 incorrespondence with the display storage amount of the VGA display signalgeneration circuit 22 (see FIG. 2), and are used by the CPU 9 of thecontrol apparatus 1 to calculate equation (2).

FIG. 8 is a table showing a control command system which is generated bythe control apparatus 1 to each video camera 13. The table has addressesassociated with apparatuses to be controlled (the video cameras 13 a to13 e) and the kinds of operation commands (focus setting, iris setting,zoom setting, rotational direction setting, and the like), and eachcontrol command is transmitted from the interface controller 12 to eachvideo camera 13. Note that control commands associated with pan and tiltmovements are controlled by utilizing U_(X) (X=0 to 6), as can be seenfrom operation commands shown in FIG. 8.

FIG. 9 is a table showing the status format of each video camera 13. Ina status code, one of M0 indicating “operation finished” and M1indicating “now operating” is stored. Status information from each videocamera is sequentially transmitted from the external interface circuit43 of each video camera 13 to the interface controller 12 of the controlapparatus 1 in the order of a camera apparatus number, information kindcode (CA), and status code.

FIG. 10 is a table showing the function format of each video camera 13.Function information from each video camera 13 is sequentiallytransmitted from its external interface circuit 43 to the interfacecontroller 12 of the control apparatus 1 in the order of a cameraapparatus number, information kind code (CA), sensor size, horizontalmoving range angle, vertical moving range angle, and video signal form,and the moving angle θ of the video camera 13 is calculated on the basisof equations (1) to (3) above.

The control sequence of the control apparatus of this embodiment will bedescribed in detail below with reference to the flow charts in FIGS. 11to 13 and FIG. 4.

The power switches of the video cameras 13 a to 13 e and the controlapparatus 1 are turned on to start a control software program (step S1).A counter m of the switch 55 is set to be 1, and a selection number n ofthe input video camera is set to be 1 (step S2). When the counter m ofthe switch 55 is set to be “1”, the terminal 56 a serves as a video andoperation control line; when the counter m of the switch 55 is set to be“2”, the terminal 56 b serves as a video and operation control line;when the counter m of the switch 55 is set to be “3”, the terminal 56 cserves as a video and operation control line; and the same applies toother terminals. On the other hand, when the selection number n of thevideo camera is set to be “1”, the video camera 13 a becomes anapparatus to be controlled; when the selection number n of the videocamera is set to be “2”, the video camera 13 b becomes an apparatus tobe controlled; when the selection number n of the video camera is set tobe “3”, the video camera 13 c becomes an apparatus to be controlled; andthe same applies to other video cameras.

In step S3, the switch 55 is connected to the video and operationcontrol line m of the video camera n.

An initialization command (I0) is supplied via the external interfacecircuit 43 (FIG. 3) of the video camera 13 to set the direction of thevideo camera to have the pan angle=0 and the tilt angle=0 (step S4).Note that leaf switches (not shown) are respectively attached to thepositions corresponding to the pan and tilt angles=0, a pan maximummoving position, and a tilt maximum moving position. When the pancontrol motor 40 and the tilt control motor 42 are driven and these leafswitches are turned on, the operation processing unit 44 recognizes anabsolute position. The pan control motor 40 and the tilt control motor42 are driven from this recognized position to set the movable portion34 at an initial position.

The control apparatus 1 supplies a status signal return command (T0) tothe video camera 13 via the external interface circuit 43 (step S5), andchecks in step S6 if initialization is completed. When initialization isnot completed, the video camera 13 sends a status code M1 indicating“now operating” to the control apparatus 1, and the control apparatus 1is set in a standby state. When initialization is completed, the videocamera 13 sends back an operation end status code M0 to the controlapparatus 1, and the flow advances to step S7. At this time, the controlapparatus 1 causes the monitor 11 to display a camera view icon of thevideo camera 13 a to inform to an operator that the video camera 13 a isoperable.

In step S7, a camera function request command (T1) is supplied from theinterface controller 12 to the video camera 13 a. It is then checked ifcamera function information is sent to the control apparatus 1. When thecamera function information is not sent yet, the control apparatus 1waits for a predetermined period of time until the information is sent(step S8). This wait time is counted by a timer, and when theabove-mentioned function information (see FIG. 10) is sent during thecount operation of the timer, the flow advances to step S9 in FIG. 12 tostore the received function information in the storage unit 2 in thecontrol apparatus 1. Furthermore, a view icon corresponding to thefunction of the video camera 13 a is displayed on the monitor 11.

The flow then advances to step S10 to increment the counter m of theswitch 55 and the selection number n of the video camera by “1” toswitch the switch 55, and it is checked if the functions of all thevideo cameras are read (step S11).

If the functions of all the cameras are not read yet, the flow returnsto step S3 to repeat the processing in steps S3 to S10; otherwise, it ischecked if the view icon of the video camera 13 a is double-clicked bythe mouse 15 (step S12). If NO in step S12, the flow advances to stepS15 (FIG. 13); otherwise, a command for displaying a video image on thedisplay picture 59 is supplied to the superimposing controller 17 viathe bus 8 (step S13), thereby displaying an image on the display picture59 (step S14).

The read-out operations of the function information can be similarlyperformed for the remaining video cameras 13 b to 13 e. On the otherhand, if the reception timer of the status information and the functioninformation reaches a time-out state in step S8, it is determined thatthe corresponding video camera has no movable portion. Morespecifically, a video camera which causes a time-out state has neitherthe pan function nor the tilt function.

It is checked in step S15 if the pan control cursor 61 is designated. IfNO in step S15, the flow advances to step S17; otherwise, the movingangle θ, in the pan direction, of the video camera 13 a is calculated incorrespondence with the absolute position of the pan control cursor 61,and an absolute moving angle is supplied from the interface controller12 to the video camera 13 a using a U5+ extension to change the angle(step S16). Thereafter, the flow jumps to step S23.

Similarly, it is checked in step S17 if the tilt control cursor 63 isdesignated. If NO in step S17, the flow advances to step S19; otherwise,the moving angle θ, in the tilt direction, of the video camera 13 a iscalculated in correspondence with the absolute position of the tiltcontrol cursor 63, and an absolute moving angle is supplied from theinterface controller 12 to the video camera 13 a using a U6+ extensionto change the angle (step S18). Thereafter, the flow jumps to step S23.

Similarly, it is checked in step S19 if the iris control cursor 60 isdesignated. If NO in step 819, the flow advances to step S21; otherwise,the iris amount of the video camera 13 a is calculated in correspondencewith the absolute position of the iris control cursor 60, and anabsolute iris value is supplied from the interface controller 12 to thevideo camera 13 a using an E5+ extension (step 820). Thereafter, theflow jumps to step S23. More specifically, the iris full open positioncorresponds to the leftmost position of the cursor, the iris fullstop-down position corresponds to the rightmost position of the cursor,and an intermediate iris position is proportionally allocated incorrespondence with each different cursor position.

Similarly, it is checked in step S21 if the zoom control cursor 62 isdesignated. If NO in step S21, the flow returns to step S12; otherwise,the zoom amount of the video camera 13 a is calculated in correspondencewith the absolute position of the zoom control cursor 62, and anabsolute zoom value is supplied from the interface controller 12 to thevideo camera 13 a using a Z5+ extension (step S22). Thereafter, the flowjumps to step S23. More specifically, the interval between maximum andminimum zoom positions is proportionally allocated in correspondencewith different positions of the zoom control cursor 62 as in the controlof the iris control cursor 60.

In step S23, a status signal return request command (T0) is sent fromthe interface controller 12 to the video camera 13 a to check theexecution state of the above-mentioned camera operation control command,and it is then checked if a status signal indicating completion ofexecution of the command is returned (step S24). More specifically, thecontrol waits for input of a status signal indicating completion ofexecution of the command from the video camera, and when execution ofthe command is completed, the flow returns to step S11 to continue theprocessing. By switching the switch 55, the above-mentioned operation issimilarly performed for the remaining video cameras 13 b to 13 e.

In this manner, after the power switches of the video cameras 13 a to 13e are turned on, function information such as the size of the CCD 53,the pan/tilt movable range, and the like of each of the video cameras 13a to 13 e is supplied to the control apparatus, and the operations ofthe plurality of video cameras 13 a to 13 e can be controlled inaccordance with the function information. For this reason, a man-machineinterface corresponding to the functions of the video cameras 13 can beconstituted. More specifically, when the video cameras 13 a to 13 e havedifferent function information, the operator M need not switch a devicedriver software program in correspondence with the video cameras 13 a to13 e to execute control, thus improving convenience. The load on theoperator is reduced, and the operator can accurately and efficientlycontrol the photographing operations of various video cameras by asimple operation while observing the display picture 59 on the monitor11.

FIG. 14 is a block diagram showing an image synthesization circuit 10 asthe second embodiment of a control apparatus according to the presentinvention. The same reference numerals in FIG. 14 denote the same partsas in FIG. 2, and a detailed description thereof will be omitted. InFIG. 14, a still image storing unit 64 for storing a video signal outputfrom each of the video cameras 13 a to 13 e as a still image is added.More specifically, the still image storing unit 64 is connected to theA/D converter 25, the digital video decoder 26, the PLL circuit 31, themirror image conversion circuit 27, the superimposing controller 17, andthe TTL switch 28. The storing unit 64 receives a video signal outputfrom each of the video cameras 13 a to 13 e, and also receives a controlsignal from each video camera 13 via the interface controller 12, thebus 8, and the superimposing controller 17. More specifically, as shownin FIG. 15, the still image storing unit 64 sequentially stores positioninformation signals indicating a pan angle (+α), a tilt angle (0), azoom angle of view (W1), and the like which are input in this order fromeach video camera 13.

In the second embodiment, as shown in FIG. 16, the monitor 11 has astill image trigger key 65 and a still image display picture 66 inaddition to the moving image display picture 59 for displaying a movingimage picked up by the video camera. The still image display picture 66displays a still image which is read out upon operation of the stillimage trigger key 65.

FIGS. 17A and 17B show the positional relationship between an imagedisplayed on the still image display picture 66 upon operation of thestill image trigger key 65, and object persons at that time. FIG. 17Ashows the still image, and FIG. 17B is a plan view of a photographingroom.

More specifically, after the power switch of the video camera 13 a isturned on and the video camera 13 a is initialized, the direction of thevideo camera 13 a is set at an initialize position I. When the pancontrol cursor 61 is dragged by operating the mouse 15 and the stillimage trigger key 65 is clicked at a position rotated by (+α) in the pandirection, the image shown in FIG. 17A is stored in the still imagestoring unit 64. More specifically, the still image storing unit 64stores position information signals indicating the pan angle (+α), thetilt angle (0), the zoom angle of view (W1), and the like in this order,as described above. When the video camera 13 a is rotated by (η−α) inthe pan direction by moving the pan control cursor 61 and the zoomcontrol cursor 62 so as to be directed in the direction of an objectperson A, as shown in FIG. 18B, the zoom angle of view changes from theangle WI of view to an angle W2 of view, and this change amount isstored in the storage unit 2.

When an object person A is zoomed up from this camera position whilemaintaining the zoom angle W2 of view, the pan control cursor 60 and thelike may be moved by controlling the mouse 15 as in a case wherein theobject person B is displayed at the central position. However, if thecursor is moved each time the direction of the video camera is changed,this results in a cumbersome operation and a heavy load on an operatorespecially in, e.g., a video conference in which different persons speakby turns. Thus, in this embodiment, as shown in FIG. 18A, the mouse 15is clicked in a state wherein the object person A is zoomed up and themouse cursor 15 a is maintained at a position shown in FIG. 16 so as torealize direction control of the video camera toward the still objectperson A. Similarly, as shown in FIG. 19B, when the video camera 13 a isrotated by −(η+β) from the current position in the pan direction, thevideo camera 13 a can be direction-controlled toward the object personC. Similarly, when a camera movement in the tilt direction is to beattained, the video camera can be controlled to a target position bydesignating an upper or lower position of the still image displaypicture 66.

FIGS. 20 to 23 are flow charts showing the control sequence of thesecond embodiment.

The power switches of the video camera 13 a and the control apparatus 1are turned on (steps S31 and S32). The control apparatus 1 supplies aninitialization command (I0) to the video camera 13 a via the externalinterface circuit 43 (FIG. 3) to set the direction of the video camera13 a at an initial position (the pan angle=0 and the tilt angle=0) (stepS33). The control apparatus 1 supplies a status signal return requestcommand (T0) to the video camera 13 a via the external interface circuit43 (step S34) and checks if initialization is completed (step S35). IfNO in step S35, flow returns to step S34 to wait for completion of theinitialization; otherwise, the video camera 13 a returns aninitialization end status signal to inform to the control apparatus 1that the video camera 13 a is operable. The CPU 9 supplies a command fordisplaying a photographed image on the display picture 59 to thesuperimposing controller 17 via the bus 8 (step S36), and an imagephotographed by the video camera 13 a is displayed on the displaypicture 59 (step S37).

The flow then advances to step S38 in FIG. 21, and the zoom lens 49 ismoved by controlling the pan control motor 40, the tilt control motor42, and the zoom control circuit 50 of the video camera 13 a using thepan control cursor 61, the tilt control cursor 63, and the zoom controlcursor 62 until all object persons A, B, and C are photographed togetherby one camera picture (step S38). It is then checked if the mouse 15clicks the still image trigger key 65 (step S39). If NO in step S39, theflow advances to step S42 (FIG. 22); otherwise, the object persons A, B,and C are displayed on the display picture 59, the video signal from thevideo camera 13 a at that time is stored in the still image storing unit64, and a command is issued to the superimposing controller 17 to readout the stored still image and to display the readout still image on thestill image display picture 66 (step S40). The flow then advances tostep S41 to store the pan/tilt/zoom positions at that time in the stillimage storing unit 64.

It is checked in step S42 if the pan control cursor 61 is designated. IfNO in step S42, the flow advances to step S44; otherwise, the movingangle θ, in the pan direction, of the video camera 13 a is calculated incorrespondence with the absolute position of the pan control cursor 61,and an absolute moving angle is supplied to the video camera 13 a usinga U5+ extension to change the angle (step S43). Thereafter, the flowjumps to step S48.

Similarly, it is checked in step S44 if the tilt control cursor 63 isdesignated. If NO in step S44, the flow advances to step S46; otherwise,the moving angle θ, in the tilt direction, of the video camera 13 a iscalculated in correspondence with the absolute position of the tiltcontrol cursor 63, and an absolute moving angle is supplied to the videocamera 13 a using a U6+ extension to change the angle (step S45).Thereafter, the flow jumps to step S48.

Similarly, it is checked in step S46 if the zoom control cursor 62 isdesignated. If NO in step S46, the flow returns to step S50; otherwise,the zoom amount of the video camera 13 a is calculated in correspondencewith the absolute position of the zoom control cursor 62, and anabsolute zoom value is supplied to the video camera 13 a using a Z5+extension (step S47). Thereafter, the flow jumps to step S48. Morespecifically, the interval between maximum and minimum zoom positions isproportionally allocated in correspondence with different positions ofthe zoom control cursor 62.

In step S48, a status signal return request command (T0) is sent to thevideo camera 13 a to check the execution state of the above-mentionedcamera operation control command, and it is then checked if a statussignal indicating completion of execution of the command is returned(step S49). More specifically, the control waits for input of a statussignal indicating completion of execution of the command from the videocamera, and when execution of the command is completed, the flowadvances to step S50 (FIG. 23) to check if the mouse is clicked in therange of the still image display picture 66. If NO in step S50, the flowreturns to step S39; otherwise, the still image position information isread out from the still image storing unit 64 (step S51), and adifference between the central position of the still image and thedesignated position is calculated by the pointing position recognizingcircuit 19 (step S52).

The angle difference from the current camera position to the targetposition is then calculated (step S53), and the pan control motor 40 andthe tilt control motor 42 are driven to move the video camera to thetarget position (step S54). Then, a status signal return request commandT0 is sent to the video camera 13 a (step S55) and it is checked ifexecution of the command is completed (step S56). If NO in step S56, thecontrol waits for completion of execution of the command; otherwise, theflow returns to step S39 to repeat the above-mentioned processing.

As described above, according to the second embodiment, an imagephotographed by the video camera 13 a and a still image aresimultaneously displayed on windows on the monitor 11, and when arequired position on the still image is designated by the mouse 15, thephotographing operation of the video camera 13 a is controlled, so thatthe required position is located at the center of the moving image. Whenthe pan control cursor 61, the tilt control cursor 63, and the zoomcontrol cursor 62 displayed on the display picture 59 on the monitor 11are designated and controlled by the mouse 15, the display control of avideo image can be attained. For this reason, the load on an operatorcan be reduced by a simple operation, and the photographing operation ofthe video camera can be accurately and efficiently performed with anatural feeling while observing an image displayed on the monitor 11.More specifically, an object is photographed at a wide-angle zoomposition, the photographed image is displayed as a still image, and thedirection control of the camera can be easily realized by operating themouse in the picture of the still image displayed on the monitor 11.

As described above, in the second embodiment, in control of the camerahaving a rotary mechanism portion such as a tripod, the direction of thecamera can be easily controlled to a required object person byphotographing an object at a wide-angle zoom position and pointing theposition of the required object person in the photographed imagedisplayed as a still image on the monitor.

The third embodiment of the present invention will be described belowwith reference to FIGS. 24 and 25.

FIG. 24 is a block diagram showing a control apparatus for a videocamera according to the third embodiment of the present invention. Thesame reference numerals in FIG. 24 denote the same parts as in FIG. 1,and a detailed description thereof will be omitted. A local terminal anda remote terminal are connected via a communication network N such as anISDN line or a LAN line. More specifically, the communication network Nis connected to the bus 8 of the control apparatus 1 via a networkconnection interface 67. A moving image CODEC 68 is connected betweenthe bus 8 and the network interface 67, and is connected to the videoimage synthesization circuit 10 via a switch 69. A control commandtransmitted from a video camera in the remote station via thecommunication network N is supplied onto the bus 8. On the other hand,moving image data transmitted from the video camera in the remotestation is expanded by the moving image CODEC 68, the expanded data istransmitted to the image synthesization circuit 10 via the switch 69,and the video signal is output to the monitor 11. Moving imageinformation output from the video camera 13 in the local station iscompressed by the moving image CODEC 68, and is transmitted to the videocamera in the remote station via the communication network N. In thismanner, intercommunications can be performed by compressing/expandinginformation on the communication network to reduce the informationamount.

FIG. 25 shows the operation state and the display state of the thirdembodiment.

More specifically, the monitor 11 has the still image display picture66, the still image trigger key 65, a local station image display screen70, and a remote station image display screen 71, and the display stateof the local and remote station image display screens 70 and 71 can becontrolled on the monitor 11 by operating the mouse 15 connected to thecontrol apparatus 1 of the local station. The moving image CODEC 68 isdetachable from the control apparatus 1, and can be attached to aterminal (not shown) provided to the back surface side of the controlapparatus 1.

As described above, according to the third embodiment, a local terminaland a remote terminal are connected to each other via the communicationnetwork N, and each terminal is provided with the control apparatus 1comprising the monitor 11. When the control apparatus 1 is controlled bythe mouse 15 in at least one terminal, a local station moving image, andmoving and still images from the video camera in the remote station canbe simultaneously displayed on windows on the picture of the monitor 11.In this state, when a required pixel position of the still image displaypicture 66 is designated by the mouse cursor 15 a by operating the mouse15, the photographing operation of the video camera 13 can be controlledto locate the designated position at the center of the picture. In thismanner, in the third embodiment as well, the load on an operator can bereduced by a simple operation, and the photographing operation of thevideo camera can be accurately and efficiently performed with a naturalfeeling while observing an image displayed on the monitor 11.

FIG. 26 is a block diagram showing the arrangement of a video camerawith pan and tilt functions according to the fourth embodiment of thepresent invention. Referring to FIG. 26, a video circuit portion 110Bcontrols a camera head movable portion 110A, and processes an imagesignal therefrom.

The camera head movable portion 110A includes a zoom lens 112, an iriscontrol circuit 114 for controlling a light amount, a focus controlcircuit 116 for controlling the focusing position of the zoom lens 112,a zoom control circuit 118 for controlling the magnification of the zoomlens 112, an image pickup element 120 for converting an optical imagefrom the zoom lens 112 into electrical signals in units of pixels, and aread-out circuit 122 for sequentially reading out the electrical signalsfrom the image pickup element 120.

The camera head movable portion 110A also includes a tilt directiondrive device 124, comprising, e.g., a stepping motor and the like, fordriving the camera head movable portion 110A in the tilt direction, aclock generation circuit 126 for generating clocks for the image pickupelement 120, and a camera head CPU 128 for controlling the iris controlcircuit 114, the focus control circuit 116, and the zoom control circuit118 in accordance with a control signal from the video circuit portion110B.

The video circuit portion 110B includes a pan direction drive device130, comprising, e.g., a stepping motor and the like, for rotating thecamera head movable portion 110A in the pan direction, a motor drivecircuit 132 for controlling the motors in the tilt and pan directiondrive devices 124 and 130, and a process circuit 134 for generatingluminance and chrominance signals on the basis of the output from theread-out circuit 122 in the camera head movable portion 110A.

The video circuit portion 110B also includes an image storing unit 136for storing all images in a movable range of the camera head movableportion 110A on the basis of the output from the process circuit 134, aswitch 138 for selecting one of the outputs from the process circuit 134and the image storing unit 136, a video encoder 140 for converting theoutput from the switch 138 into a video signal of a predeterminedstandard, a pointing mark generation circuit 142 for generating apointing mark as an arrow or a marker to be displayed on the picture, anadder 144 for adding the output from the pointing mark generationcircuit 142 to the output from the video encoder 140, and a video outputterminal 146 for outputting the output from the adder 144 to an externaldevice.

The video circuit portion 110B further includes a CPU 148 forcontrolling the entire apparatus, an I/O port 150 for supplying acontrol signal output from the CPU 148 to the respective units, anexternal interface 152 for interfacing communications between anexternal control device and the CPU 148, a connection terminal 154 forconnecting the external control device, and a nonvolatile memory 156 forstoring information of a photographing prohibition region, andinformation inherent to the apparatus. The nonvolatile memory 156comprises, e.g., an EEPROM (electrically erasable programmable read onlymemory), a battery-backed up D-RAM, an S-RAM (static random accessmemory), or the like.

The video circuit portion 110B also includes switches 158 including anall photographing picture image display switch 158 a, a photographingprohibition setting switch 158 b, a left-move switch 158 c, a right-moveswitch 158 d, an up-move switch 158 e, and a down-move switch 158 f.

The video circuit portion 110B also includes a power supply inputterminal 160 and a DC-DC converter 162 for generating a DC voltagerequired for the respective units from a DC voltage input from the powersupply input terminal 160.

FIG. 27 is a view showing a state wherein a video conference is heldusing this embodiment, and FIG. 28 shows a display example of themonitor picture.

FIG. 29 is a perspective view of the drive device in the camera headmovable portion 110A. FIGS. 30, 31, 32, and 33 are plan views showingthe photographing angles of view at respective pan positions. In thisembodiment, a horizontal photographable range can be covered by four panoperations. FIG. 34 is a side view showing movement of a camera 110 inthe tilt direction. FIG. 35 shows a display example of allphotographable range picture images.

FIG. 36 is a diagram showing the internal circuit of the image storingunit 136. The image storing unit 136 comprises an image signal inputterminal 210, control signal input terminals 212, 214, 216, and 218, avideo decoder 220, a filter 222, an A/D converter 224, a frame memory226, a D/A converter 228, a filter 230, an image signal output terminal232, a sync separation circuit 234, a sync signal generation circuit236, a multifreeze overlap control circuit 238, a horizontal frequencydividing circuit 240, a vertical frequency dividing circuit 242, ahorizontal address counter 244, an offset X address buffer 246, an adder248 for adding an offset from the offset X address buffer 246 to theoutput address from the horizontal address counter 244, a verticaladdress counter 250, an offset Y address buffer 252, and an adder 254for adding an offset from the offset Y address buffer 252 to the outputaddress from the vertical address counter 250.

The operation of this embodiment will be described below with referenceto FIGS. 37, 38, 39, 40, 41, and 42. The power switch of the camera 110is turned on (S101). The CPU 148 sets the tilt and pan direction drivedevices 124 and 130 at initial positions via the I/O port 150 and themotor drive circuit 132 (S102). The CPU 148 outputs an operation startcommand to the camera head CPU 128 in the camera head movable portion110A (S103).

The camera head CPU 128 controls the iris control circuit 114 and awhite balance circuit (not shown) to adjust the exposure amount andwhite balance in correspondence with an external environment (S104).Upon completion of the iris control and white balance control, thecamera head CPU 128 enables the clock generation circuit 126 to causethe image pickup element 120 to start photoelectric conversion. Theimage pickup element 120 converts an optical image from the zoom lens112 into electrical signals. The read-out circuit 122 sequentially readsout the electrical signals from the image pickup element 120 in responseto the clocks from the clock generation circuit 126, and transfers themto the process circuit 134 (S106). The CPU 148 connects the switch 138to a terminal b via the I/O port 150 (S107). When the switch 138 isconnected to the terminal b, a video signal of an object is output fromthe video output terminal 146 to an external device (S108).

The CPU 148 checks if the all photographing picture image display switch158 a is depressed (S109). When the switch 158 a is continuouslydepressed for 3 seconds or more (S113), the CPU 148 generates images ina photographable range of the video camera 110 by all photographingpicture image formation processing (S114). When the all photographingpicture image display switch 158 a is released in less than 3 seconds(S113), a flag MODE indicating whether or not an all photographingpicture image display mode is set is checked (S115). If the flag MODE is‘0’, the all photographing picture image display mode is set (S116); ifthe flag MODE is ‘0’, the all photographing picture image display modeis canceled (S123 and S124).

Photographing prohibition picture setting processing will be describedbelow. It is checked if images in a photographable range are alreadystored in the image storing unit 136 (S116). If N (NO) in step S116, theflow returns to step S114; otherwise, the switch 138 is switched to aterminal a side, so that the images stored in the image storing unit 136are output from the video output terminal 146 (S117). It is checked ifone of the move switches 158 c, 158 d, 158 e, and 158 f is depressed(S118). If N in step S118, the flow advances to step S120; otherwise, aphotographing prohibition setting cursor is displayed, and is moved inthe designated direction (S119), as shown in FIG. 43. The photographingprohibition setting cursor is generated by the pointing mark generationcircuit 142 in accordance with an instruction from the CPU 148, and theadder 144 superimposes the cursor on a video signal of an image storedin the image storing unit 136.

It is checked if the photographing prohibition setting switch 158 b isdepressed (S120). If N in step S120, the flow advances to step S122;otherwise, the luminance of the pictures which is set in thephotographing prohibition mode is lowered as compared to other picturesfree from the photographing prohibition mode, as indicated by grayportions in FIG. 43 (S121). In FIG. 43, objects A and B are set in thephotographing prohibition mode. Thus, the photographing prohibitionpictures can be confirmed at a glance. In addition, the pan and tiltangles of image freeze positions and zoom magnification informationstored in the nonvolatile memory 156 are stored in another area in thenonvolatile memory 156 in correspondence with the photographingprohibition pictures. Thereafter, ‘1’ is set in the mode discriminationflag MODE.

FIG. 41 is a flow chart showing in detail the all photographable pictureimage formation processing in step S114 in FIG. 39. The CPU 148 fetchescontrol values (focal length information f and zoom magnification) ofthe focus control circuit 116 and the zoom control circuit 118 from thecamera head CPU 128 via the I/O port 150, and calculates horizontal andvertical photographable angles Wp and Wt of view of the image pickupelement 120 at that time using the following equations by a method inFIG. 44, which is the same as that in FIG. 7 in the first embodiment(S131).X/2f=tan(Wp/2)  (4)Y/2f=tan(Wt/2)  (5)where X is the horizontal effective image size of the image pickupelement 120, and Y is the vertical effective image size.

Then, divided image numbers Np and Nt in the pan and tilt directions ofmulti-pictures in the image storing unit 136 are calculated (S132). Ifthe movable angle, in the pan direction, of the camera 110 isrepresented by θpmax and the movable angle, in the tilt direction,thereof is represented by θtmax, the numbers Np and Nt are respectivelygiven by:Np=[θpmax/Wp]  (6)Nt=[θtmax/Wt]  (7)where [X] is an integer equal to or smaller than X+1 and larger than X.If the current position of the pan angle is represented by θp and thecurrent position of the tilt angle is represented by θt, the camera headmovable portion 110A is moved and set so as to attain θp=0 and θt=0(S132). Note that θp=0 corresponds to the state shown in FIG. 30, andθt=0 corresponds to a position a in FIG. 34.

Freeze counters CNfp and CNft in the pan and tilt directions areinitialized (S133). That is,CNfp=0  (8)CNft=0  (9)

The value of the freeze position is set in the offset X and Y addressbuffers 246 and 252 of the image storing unit 136 (S134). The CPU 148instructs the sync signal generation circuit 236 in the image storingunit 136 via the I/O port 150 to output an image freeze timing signal.The CPU 148 stores the pan angle θp, the tilt angle θt, and the zoomposition information in the image freeze state in the nonvolatile memory156, and utilizes this information in control of the photographingprohibition range in a normal camera control mode (S135).

The pan direction counter CNfp is incremented (S136). An image isrotated by θpmax/Np in the pan direction, and is frozen at a positiongiven by (S137):θp=θp+θpmax/Np  (10)

The count of the pan direction counter CNfp is compared with themulti-picture image number Np in the pan direction to check if the imagefreeze operation in the pan direction is completed (S138). If N in stepS138, the flow returns to step S134 to repeat step S134 and subsequentsteps (see FIGS. 31 and 32).

Upon completion of fetching of an image in the pan direction (see FIG.33), the tilt direction counter CNft is incremented (S139), and thecamera head movable portion 110A is directed to a position of the pandirection angle θp=0 (S140). An image is rotated by θtmax/Nt in the tiltdirection (S141). Please refer to a position b in FIG. 34.

The count of the tilt direction counter CNft is compared with themulti-picture image number Nt in the tilt direction to check if theimage freeze operation in the tilt direction is completed (S142). If Nin step S142, the flow returns to step S134 to repeat step S134 andsubsequent steps.

With the above-mentioned operation, all photographable ranges of thecamera 110 are photographed in turn to form images of all photographablepictures. FIG. 35 shows an example of all the completed photographablepicture images. In this case, four pictures in the horizontal directionand three pictures in the vertical direction are used. However, thepresent invention is not limited to these numbers of pictures.

FIG. 42 is a flow chart showing in detail the processing in step S112 inFIG. 38. Upon operation of the move switch 158 c, 158 d, 158 e, or 158 f(or in response to a similar operation command from an external device),the camera head movable portion 110A is moved in the pan and tiltdirection to update the pan angle θp and the tilt angle θt (S151). Thephotographing prohibition range information is read out from thenonvolatile memory (S152). When the focal length has been changed due toa change in zoom magnification (S153), the photographing prohibitionrange information read out from the nonvolatile memory 156 is correctedin correspondence with the change in focal length (S154). If the currentpan and tilt angles fall outside the photographing prohibition range(S155), a video output operation is permitted; otherwise, the videooutput operation is prohibited.

For example, as shown in FIG. 45, a 3-terminal switch 139 is arranged inplace of the switch 138, and the output from an image storing unit 137for storing a still image is connected to a terminal c of the switch139. If the current pan and tilt angles fall outside the photographingprohibition range (S155), the switch 139 is connected to a terminal b tovideo-output a photographed image (S156); otherwise, the switch 139 isconnected to the terminal c to video-output a still image stored in theimage storing unit 137 (S157).

FIG. 46 shows a video image superimposing circuit connected to the busof a personal computer or workstation, and this circuit can have afunction of the image storing unit 136 shown in FIG. 36. With thiscircuit, the camera 110 need only have a function of outputting aphotographed image.

Referring to FIG. 46, an input terminal 300 receives an analog videosignal complying with the NTSC/PAL/SECAM system. An A/D converter 302converts an analog video signal from the input terminal 300 into adigital signal. A digital video decoder 304 converts the output from theA/D converter 302 into RGB signals, and supplies the RGB signals to amirror image conversion circuit 305. In accordance with an externalcontrol signal, the mirror image conversion circuit 305 supplies theoutputs from the decoder 304 to a synthesization control circuit 306with or without reversal in the horizontal direction. A PLL circuit 308supplies clocks of a predetermined frequency to the A/D converter 302,the video decoder 304, the mirror image conversion circuit 305, and thesynthesization control circuit 306.

Data on a bus 310 of the personal computer or workstation is supplied tothe synthesization control circuit 306 via a buffer 312, andaddress/control signals are directly supplied to the synthesizationcontrol circuit 306. Also, the data and address/control signals on thebus 310 are also supplied to a VGA display signal generation circuit 316via a bus interface 314. The VGA display signal generation circuit 316generates VGA image data of an image stored in a memory 320 inaccordance with a timing signal from a display timing generation circuit318. The generated image data is supplied to the synthesization controlcircuit 306 and a color palette 322. The color palette 322 outputs RGBimage data in accordance with data from the circuit 316.

The synthesization control circuit 306 writes the RGB data from thevideo decoder 304 in a video memory 324, and generates a switchingcontrol signal of a switch circuit 326 in accordance with theaddress/control signals form the bus 310. The switch circuit 326 selectsthe RGB outputs from the color palette 322 or the RGB data from thevideo memory 324 in accordance with the switching control signal, andoutputs selected data to a D/A converter 328. The D/A converter 328converts digital data into an analog signal. An image signal which issynthesized as described above is supplied to a monitor 132 via anoutput terminal 330, and is displayed on a picture 134.

In the all photographable picture image formation mode, thesynthesization control circuit 306 stores images of video signals inputto the input terminal 300 in an all photographing range images memory325. More specifically, the all photographing range images memory 325has the same function as the image storing unit 136. When allphotographable picture images stored in the all photographing rangeimages memory 325 are to be output, the synthesization control circuit306 sequentially reads out image data stored in the memory 325, andtransfers them to the switch 326 via the VRAM 324. In this manner, thesame function as the image storing unit 136 and the switch 138 can berealized by the circuit shown in FIG. 46.

In the example shown in FIG. 43, the multifreeze overlap control circuit238 in FIG. 36 can eliminate boundaries among images. FIG. 47 shows animage without boundaries.

FIG. 48 shows the transmission format of control commands for externallycontrolling the camera 110. The CPU 148 performs iris, focus, zoom, pan,and tilt control in accordance with the control commands in the formatshown in FIG. 48. The control command consists of an identifier (“:” inthis case), information of an apparatus to be controlled (3 bytes), thekind of operation command (2 bytes), an extension flag, and the like.

The present invention is not limited to the above embodiments, andvarious changes and modifications may be made within the spirit andscope of the invention. In each of the above embodiments, an imageposition is designated using a mouse but may be designated using acombination of a digitizer and an input pen. In each of the aboveembodiments, the moving angle to a target object may be calculated athigh speed by a special-purpose circuit.

1. A video system comprising: an image pickup control device thatcontrols an image pickup operation of an image pickup device; a displaycontrol device that displays an image to indicate a photographable rangeof the image pickup operation of the image pickup device, on a screen; arange setting device that sets a desired image portion of the imagedisplayed by said display control device on the screen, thereby settinga restricted photographable range of the image pickup operation intosaid image pickup control device on the basis of the set desired imageportion; and an image processing device that exchanges the set desiredimage portion of the image displayed by said display control device, foranother image.
 2. A video system according to claim 1, wherein theanother image is a predetermined still image.
 3. A video systemaccording to claim 1, further comprising a display device that displaysthe image picked up by the image pickup device, wherein thephotographable range of the image pickup operation image is larger thana range of the image to be displayed on said display device.
 4. A videosystem according to claim 1, wherein said range setting device sets therestricted photographable range in response to designation of acorresponding portion on the image indicating the photographable rangeof the image pickup operation.
 5. A video system comprising: an imagepickup control device that controls an image pickup operation of animage pickup device; a display control device that displays an image toindicate a photographable range of the image pickup operation of theimage pickup device, on a screen; a range setting device that sets adesired image portion on the image displayed by said display controldevice on the screen, thereby setting a restricted photographable rangeof the image pickup operation into said image pickup control device onthe basis of the set desired image portion; and a restriction devicethat restricts an amount of data corresponding to the set desired imageportion of the image displayed by said display control device.
 6. Avideo system according to claim 5, further comprising a display devicethat displays the image picked up by the image pickup device, whereinsaid restriction device restricts the amount of data in order that noimage data of the image picked up by the image pickup device is outputto said display device.
 7. A video system according to claim 5, furthercomprising a display device that displays the image picked up by theimage pickup device, wherein the photographable range of the imagepickup operation image is larger than a range of the image to bedisplayed on said display device.
 8. A video system according to claim5, wherein said range setting device sets the restricted photographablerange in response to designation of a corresponding portion on the imageindicating the photographable range of the image pickup operation.
 9. Avideo system control method comprising the steps of: controlling animage pickup operation of an image pickup device; displaying an image toindicate a photographable range of the image pickup operation of theimage pickup device, on a screen; setting a desired image portion of theimage displayed in said displaying step on the screen, thereby setting arestricted photographable range of the image pickup operation into saidcontrolling step on the basis of the set desired image portion; andexchanging the set desired image portion of the image displayed in saiddisplaying step, for another image.
 10. A video system control methodcomprising the steps of: controlling an image pickup operation of animage pickup device; displaying an image to indicate a photographablerange of the image pickup operation of the image pickup device, on ascreen; setting a desired image portion of the image displayed in saiddisplaying step on the screen, thereby setting a restrictedphotographable range of the image pickup operation into said controllingstep on the basis of the set desired image portion; and restricting anamount of data corresponding to the set desired image portion of theimage displayed in said displaying step.
 11. A computer readablerecording medium having recorded thereon a computer-executable programfor making a computer execute a video system control method comprisingthe steps of: controlling an image pickup operation of an image pickupdevice; displaying an image to indicate a photographable range of theimage pickup operation of the image pickup device, on a screen; settinga desired image portion of the image displayed in said displaying stepon the screen, thereby setting a restricted photographable range of theimage pickup operation into said controlling step on the basis of theset desired image portion; and exchanging the set desired image portionof the image displayed in said displaying step, for another image.
 12. Acomputer readable recording medium having recorded thereon acomputer-executable program for making a computer execute a video systemcontrol method comprising the steps of: controlling an image pickupoperation of an image pickup device; displaying an image to indicate aphotographable range of the image pickup operation of the image pickupdevice, on a screen; setting a desired image portion of the imagedisplayed in said displaying step on the screen, thereby setting arestricted photographable range of the image pickup operation into saidcontrolling step on the basis of the set desired image portion; andrestricting an amount of data corresponding to the set desired imageportion of the image displayed in said displaying step.